The most important communication channels were investigated in the situation of multiple users. These models do not assume any central intelligence there is no coordination between the transmitters, so fit to the usual conditions of an ad-hoc or sensor network. Better bounds on the minimum code word length and efficient code constructions were achieved for the scenarios, when many independent, partially active transmitters are communicating over a shared medium. These techniques can be applied in the usual code division multiple access (CDMA) situations where time and frequency resources can be utilized in one continuous domain throughout the entire communication system. Neither CDMA, nor the recently used random access protocols for conflict resolution utilize the full power of the channels. Efforts were made to obtain better bandwidth throughputs between the transmitters, to fit to the usual conditions of an ad-hoc network.